UV rays ‘may cut blood pressure’

By Paul Ward

Wednesday, May 08, 2013

The benefits of sun exposure in reducing blood pressure may outweigh the risks of developing skin cancer, research has found.

Nitric oxide, a pressure- reducing compound, is released in the blood by ultraviolet rays produced by the sun and artificial sun lamps, and can cut the risk of heart attacks and stroke, a study claims.

It was conducted by University of Edinburgh scientists who measured the blood pressure of 24 people sitting beneath UV lamps for two 20-minute sessions.

In the first session, the volunteers were exposed to the lamps’ UV rays and heat, while in the second session, the UV rays were blocked so that only the heat of the lamps affected the skin.

Blood pressure dropped significantly for one hour following exposure to UV rays but no change was recorded after the heat-only sessions, the results show.

Vitamin D had previously been thought of as the only health benefit from UV rays but the scientists say their experiments show additional positive effects.

Dr Richard Weller, senior lecturer in dermatology at the university, said: “We suspect that the benefits to heart health of sunlight will outweigh the risk of skin cancer.

“The work we have done provides a mechanism that might account for this and also explains why dietary vitamin D supplements alone will not be able to compensate for lack of sunlight.

“We now plan to look at the relative risks of heart disease and skin cancer in people who have received different amounts of sun exposure. If this confirms that sunlight reduces the death rate from all causes, we will need to reconsider our advice on sun exposure.”

Heart disease and stroke linked to high blood pressure causes around 80 times more deaths than those from skin cancer, the researchers said.

The British Association of Dermatologists said the results of the study should be treated with caution.